METHOD OF DEVELOPMENT OF NONUNIFORM OIL POOL Russian patent published in 2001 - IPC

FIELD: oil producing industry, particularly, development of nonuniform oil pools. SUBSTANCE: method includes successive injection of water shutoff compositions and displacement agent into, at least, one injection well, and oil withdrawal from, at least, one producing well. First, injected into injection well is displacement agent before drowning of oil recovered form producing well not above 5%. This oil production rate is fixed and considered as basic. Then, water shutoff compositions are injected. These compositions are used in form of polymer solution, gelling composition with initial viscosity of, at least, 3 Mpa.s/sq.m and hydrocarbon emulsion. Each water shutoff composition is periodically injected during time when oil production rate exceeds the basic one with its initial increment above basic production rate and subsequent reduction by 85-95% of registered increment. After injection of last water shutoff composition, cycle is completed and its duration in oil production above basic production rate is noted. Then, other cycles are employed with other succession of injection of water shutoff compositions. In these cases, duration of these cycles is noted under same conditions. Then, cycles are repeated. In so doing, those cycles are repeated which have maximum duration with oil production rate above basic one. EFFECT: higher efficiency of method due to increased sweep of treatment, isolation of water inflows of nonuniform pool, reduced material consumption and possible control over technological process. 1ex